Non-interfering party-line telephone system.



PATENTE W. R. BROWN. NON-NTERPBRING PARTY LINE TELEPHONE SYSTEM.

APPLICATION FILED JAN 18. 1907.

0:5 212.1 XIV! .lzlallllll .l so

' Unrrnn sirenes rnr'nnrcnnicn.-

WILLIAM- n. BROWN, or LA FAYETTE, INDIANA, AssioNon To KELLooojsWrronBoRn/AND" i l SUPPLY COMPANY, OF CHIGAGOfIv-LLINOIS, -A OORPORATI QN OF ILLINOIS.

' n'oN-n'rnnnnferne fencrnLrNnTELnPhnoNn 4sizvrsf'mrJa/f.

To all whom 'it may concer/n.: j

Beit known that I, WILLIAM R. BROWN,

'a citizen of the United States, residing in La Fayette, countycf Tippecanoe, and State of Indiana, have invented certain new and' useful Improvements :in Non-interfering Telephone Party-Lines Systems, of which the following is a speciication. j

My invention relates to systems :inwhich .means are provided whereby subscriherson the apparatnsor systems oi the above class,

and y'particulariy to provide a system in which no auxiliary a paratus such as a pushbntton is needed at the subscribers station in order to c han e the circuit arrangement from that of signa lng central to that of signaling another party; I accomplish the foregoing object by the use' of additional contacts upon the switchhoohfso connected that When the hook is in one position and the generator is rotated the circuit arrangement Wili he such es to signal the centreloperator, .and when the switch- -hookfisinits other position and the generator rctate 'the'circuitarrangement will he such as to signaithe other subscribers on. the vtele ,hone line.

lt y invention is-iiiustreted. in the eccompanying drawingjin which, Fiure l `@presents a teienh vvide With four stations cc central oiiioe terniinai 'ons si nncietor, in accordance wiihene system, 2 repone line prr- 4 4 l resents the sante Witn a monnieo. circuit arrangement.l f

Referring to Fig. '1, the iine ivires fami 4 extend from the jack 5 tothe suhstations 3, 7 8 and 9. At the central oce an impedance coil 10 of comparatively' high resistance is bridged between the limbs 3 anti i' and-hestapped from the central point of its svinlii'ne the conductor 11i Which'leads throiigh the coil of the drop 12'to ground. Each suhstn'- tion is provided with the usual bridged heit or annunciator 13, an induction coil ii, the secondary .ci which is connected in series With I the're'ceiver 15, and the primary of which is 1 connected in series' with the transmitter A161' and hatten/"17, this primary `circuit v Specification of Letters atent. iptucanon ned Jamey 1a. 1907. serai No. 362.925.

'annunciator's on the telephone line, a small v:part ci? the'currentalso passlng th'rougirtheA impedancecoil 10, but none cit passing:

i with the adapted tol he closedhyfthe removal of thereceive'r from the hook'lS, and the generatorl 9 carrying. the three-,contact-Springs,20, 21 and 22, which stand normally 4ont of'connection one With the other, but Which are adapted to 6c' be hunched by the rotation of the generator crank.v The switch-hook 18 When infits'nore mal position connects the line ,4 through contact 23 With one terminal of the enerator,l the other terminal of the'jgenerator eing con- 65 n'ected with the spring v20. 'Whenthe receiver is vremoved lfrom the hookthe contact 23 moves upward sufliciently for the Contact V24. to come into connection therewith before'. l the hooi: makes connection with 'contacts 7c in the operation yof the system of Fi the operator,4 havingl inserted her throws her ringing key 2 7 and rings allo the through'the drop `12,*v because the operatorfs generetcr' is .not grounded.' With this systern it is necessery-to use code si' ais in order ai)A to indicate which 'of the su scrib'ers on the line is desired. fihns far the 'opera-v tion ci the systemis the same as any ordi-lA nary party-line. When a subscriber desires to signal another pai-ty whom he knows to be on his `own line'y he turns his generator crank lv'vithon't removing his receiver" from] the hook. This .sends current fromA 'the' generatcr throughcontactI 20, the contacts'20,

21' and 22V being Vbnnchefi during ringing, `90,--

over conductor 28 to the line conductor 3, end from the otherpoie ofthe generator over conductor 29 and-'contact 23- of the switchhechte the other line conoluctor 4.. Thus,

thereis no tendency tothrowfthe drop 412 at th centrai'oiiice, but' the generator'current -Wi l *ass through ail ofthe annunciat'ors at* the iterent substations, and by using the proper code, thevdesired partymay he' signaled'. li, however, the subscriber desiresl'oo to ce connected vmth e. pertyjwhose Atelephone is 'not on this hne 4he :tiret removes his iver irons its hook. This connects 4'one and the contacts 20, 21 and 22 are hunched short circuit is placed about the secondary iina ci' the .'eneratorV through fthe con-' V with ground, and makes connection, between the contact 26 andthe switch-shook ,f.,

Wi/vnen the generator crank is turnedV naling .the .centraloperator without having- I' on -th'e line.

' jack 33. It is to A here discosed. Eac

lOne terminal ofthe generatorls perma` 40 theswitch-hook.'

` conductors 3-14 and 32 vuittreding i 54, the spring 54 being adaptedtolseparate ing her plug. and actuatlng her lingi scriber on another party-line the cthe second terminal of the enerator. is connected by means of thelcon uctor 28 andthe 'conductor 30 and the switch-hook with both line conductors 3 and `4 such that current from thejgen'eratorasses over conductors 3 and 4 in parallellt ough-each path of the impedance coil v conductorl 1' and thecoil of drop '12', thus throwing-this drop and-sigany` tendency to the other annunciators' In Fig. 2 a system isshown having-[the line om the `central o flice terminal 33 tothe subscribers stations 34, 35, 36 and 437. This system is provided at `thecentral office with the drop 38 'connected by conductor 39 with the line conductor 31 throu h normal contacts of the understood, lhowever, that the conductor 39 maybe permanently legged to conductor 3 1without in any Way 'interferin lwith the o eration of the system stationsv comprises the usual annunciator 40 bridged between the line conductors, 'the induction coil 41 having its secondary connected in series'with`the-receiver142, and its `primary.connected in series with the transrn/itter 43, and localbattery44, this primary circuit being ladapted to be lclosed by the removal Yof the receiver from the hook45, andthe generator 46 carry' three contact springs 47, 48 and 49, the first two of which are normally separated but adapted vto be brought into contact'by the rotation of the generator `crank, and the' second two of which are normally connected but adapted to be separated when the generatorl is in use.'v

nently connected with line' c'ondut-,tor 31 through the conductor 50, the other terminal connected with the normall Ais` lated spring 47. In addition to the usua contacts. ,'51 and' 52 associated with'the'hook-switch are the normally closed contacts 53 and from contact 53 and make connection with contact when the receiver is' removed from .In operation, the system of Fig. 2..is in ac cordance with the usual non-selective party line when the call is sent on to the 'line from the central office, the operator simply 'insertkey in accordance with thev code l'of the siiscnber 1.

ture in a brid of the subscribers ea she wishes to signal. If one of the subscribers of this line desires connection with -a` suit;` su y scriber rotates his geneiatorfcrank without Il removing his receiver from the hook. The i circuit is then completed through' the normal contacts 53 and ,54, springs 48 and 47 of the 1.

. generator, the armature of the generator, v

conductors 50, 31 and 39, .andthe coil of the drop 38 to ground. It is thus seenthat the 'diep at the man om@ be thrown' wittout signaling any of the other parties onthis same yparty line.- If, however, the calling 'subscriber wishes to signal a party,whom .he-

knows to be situated on. this same party line he first removes his receiver from its hook. This removes theground connection from spring 54 ofthe switch-hook and connects such 'spring with line conductor 32 through contact 55 and includes the generator armabtween the two. line conductors` At t e same time the movement of spring 48 severs the connection between such spring and contact 49, such that the receiver circuit is o ned and none of the generator current wi be caused to pass through the receiver,'which may or may not atths time be. at the ear of the calling'subscriber.

It is thus seen that the current will not passthrough the drop at the central oflce for the reason that there is no ground vconnection atan ofthe subscribers stations', but that the ng arty may now signal the desired substation y the use of the proper code.

I t-wi1l beiseen that the two systems here shown in Fi 1 and 2 differ both in principle of operation and in the actual manner of calling, inasmuch as in 1. the receiver is left on the hook to call t er subscribers'on the partyline, while in `ig. 2 the receiver is left lon the hoolir to ca central office. These circuit arrangements. are shown .and de-4 scribed wit respec tojce'rtain details to f which I do o twish; to be unduly limitedz it being possible to pro uce the same 'result with other lcircuiti arrang mentsl without depart-f ing from the spirit or scope of my invention.

What I cl v as new. and desireto secure by Letters atent is i --1.v Ina tel phone stem, the combination with apart teleph ne line, of a generator;

at each sub ation wherewiththe parties on i the line ma selectively signaleither central `olice or the!` other parties on` the line, and]v means dependin upon the' position of the ratus from one con tion to another,sub stantiallyas described.

vswitch-hook for c anin'g the selective appa- 2.! In 'a telephone system, the combination i withy a dpart groun ed rane tele hore line having a normally a 'the central office, a

magnetic s' aling y evice in said'grounded-'- 1 branch an anannunciator at each subscriber s station bridged between the limbs Y of the telephonefline, ay current` genera device at each subscribersl'stati'omf an means depending upon the'position'l ofthe` I f* swltch-hook fornincluding said'd'generatoteither in a'btfidge of .the line con betweenfthe telephone line 'and groundwhen the 'generator is in.. operation, substantially 3; In a telephone system, combination' Iwith a part coil bridge telephone between the line'uof animped L1100 tmbs of the uns ctors'or. l

@renee at the centrati office, e' magnetic signaling device connected between an intermediate point of said im cdance coil and a third conductor, a bri gcdannuncia-tor at each of the subscribers stations, a generating device at the subscribers station, and means depending upon the position ci the switch-hook for Connecting said generator in a bridge oi the telephone lines or between said lines and said third conductor when the generator is in operation, whereby current may be sent eit 1er through the signal at the central office or the annunciators at the other subscribers stations, substantially as described.

4. In a telephone system, the combination With a party telephone line, of a signalat the central oiiice and an annunciator at.

each of the'subscribers stations, a generetcr at `each of the subscribers7 stations, means' to direct. the current of said generator through the signal at the central oilice when the receiver hook is in one position and the generator is rotated," and means to direct the current -oi' said generator through the annunciators at the subscribers. stations Whenthe receiver hook is in the other position and the generator is rotated, substantially as described. l

5. In a telephone system, the combination with -a party'telcphone line, of a signal at the central olicc, and an annunciator at each of the subscribers stations, a generating device at each of the subscribers stations, means for directing current from seid generating device through the annunciators at the subscribers stations and for excluding the current from the central ilce signal when the -receiver hook is in one position, and means for vdirecting the current of said generator through the central oil-ice signal and excluding the current from the line annunciators when the receiver hook is in its other position, substantially as described.

6. In a telephone system, the combination with a party telephone iine, of a signal at the centrai loiiice, and an annunciator at each of the subscribers stations, a generating device at each of the subscribers stations, and Ineens for directing current from said generator through the subscribers station annunciators only when the receiver is on the hook, and ineens for directing the current of said generator through the central voiiicesignal oniy when the receiver is olii' the hook, substantially as. described.

7. .in a telephone system, the combination with a party telephone iine having means -Whereby the subscribers may attract the attention of the central oiiicc operator Without calling the other subscribers, or may call the other subscribers Without attracting the attention of the central oiiice operator, said means depending for its operation4 upon the position of the switch-hook at the caliing subscribers station, substantially as described. l

8. In a telephone system, the combination with a art tele )hone line, of ineans at the P Y i 

